Various embodiments of an underlayment for use on a roof are described herein. In particular, the embodiments described herein relate to an improved underlayment
In a typical roofing installation using asphalt shingles, an underlayer or underlayment is first applied to the plywood deck of the roof. The underlayment may take the form of an asphalt saturated paper which is useful as a waterproofing member. Roofing shingles are applied on top of the underlayment with the seams of adjacent rows positioned in an offset relationship. In practice, a starter row or strip is begun at the roof eaves using self-sealing shingles. The end of the first shingle in the strip is trimmed such that, when it is placed on the deck, the cutouts of the first course of shingles will not be placed over the starter strip joints. The starter strip and the shingles are nailed to the roof. Successive rows of shingles are then secured to the deck or roof using nails.
An underlayment may have granules embedded in an asphaltic composition. When positioned on an upper surface of the paper or membrane, the granules provide a high-traction surface upon which a roofing installer can walk. Such membranes also offer reinforcement and/or structural integrity, and allow lap sealing. Some of the granules however, may not become embedded into the asphalt material, thereby providing some amount of undesirable loose granules. Further, some embedded granules may become loose by the foot traffic of the roof installer.